I promise you it's not classified as an assault rifle. It's probably classified as an assault weapon. That's a made up term meant to cause this sort of confusion, usually defined by non functional aesthetic features like a foregrip or a heat shroud over the barrel. Its essentially a "scary looking gun" ban. The AR gets lumped in because it's one of the most common rifles in the country. It's like trying to end car crashes by banning the Honda Civic.

I bet it's classified as an assault weapon, which is different than an assault rifle.